Apron for wheeled scrapers



am 194.. T. o. DAVIDSON 2,463,523

APRON FOR WHEELED SCRAPERS Filed June 15, 1946 JNVENTOR,

A TTORNEY- Patented Mar. 8, 1949 APRON FOR WHEELED SCRAPERS Trevor 0. Davidson, Milwaukee, Wis.,

assignor to Bucyrus-Erie Company, South Milwaukee, Wis., a corporation of Delaware Application June 13, 1946, Serial No. 676,488

4 Claims. (Cl. 37-126) My invention relates to new and useful improvements in wheeled scrapers of the general type shown and described in U. S. Patent No. 2,321,410, granted June 8, 1943, to George W. Mork et al., to which patent reference is hereby made, inasmuch as this present invention represents an improvement thereon.

In scrapers of that type, the scraper fills and dumps at its front end.

The main frame of such a scraper is pivoted at either its front end or rear end to a wheeled truck, and the digging and spreading depth is determined by raising or lowering the other end with respect to a second truck. erating function.

In Mork and this present invention, the pivoting is at the front end, and the raising and lowering takes place at the rear end; but this is not essential.

The digging blade is carried rigid with the main frame, though this is not essential.

Adjacent the digging blade is pivoted a dirtextruding curved member, variously termed. For conformity with the nomenclature of the Mork patent, it will here be called a bucket. Swinging this bucket upward to dump is the second function. Returning this bucket to loadcarrying position is the third function.

There is also a front closure, known as the apron. Opening this apron (when digging or dumping), and closing it again for carrying, is the fourth function.

Mork has two controls (ropes), one of which performs the first function (namely depth-control), and the other of which successively performs the fourth function (apron opening) and the second function (dumping). For the third function (bowl return), Mork depends on a kickback cam, actuated by the fall of the apron.

My present invention is not concerned with the controls of these four functions,whether by one,

This is the first optwo, three, or four ropes, or by an hydraulic cylinder or cylinders, or otherwise.

In the conventional scraper of the general type under discussion, thelapron is opened a short distance for digging, and a considerable distance for dumping.

But, if the apron be raised sufliciently high to give a full opening, the upper edge of its bottom would interfere with the ropes or other powertransmission means extending lengthwise of the scraper.

Accordingly it is the principal object of my invention to provide an apron which will not'cause this interference, no matter how wide it is opened.

Furthermore dirt, especially if sticky, tends to pack in the apron, and not to be ejected therefrom no matter how high the apron be raised.

Accordingly a further object of my invention is to provide means for breaking the sticky material in the apron, to facilitate dumping it.

In addition to my principal objects, above stated, I have worked out a number of novel and useful details, which will be readily evident as the description progresses.

My invention consists in the novel parts and in the combination and arrangement thereof, which are defined in the appended claims, and of which one embodiment is exemplified in the accompanying drawing, which is hereinafter particularly described and explained.

Throughout the description, the same reference number is applied to the same member or to similar members.

Figure 1 is a vertical longitudinal section of my scraper in carrying position.

Figure 2 is a similar section of my scraper in dumping position.

Referring now to the figures, we see that the implement to which I have applied my invention, includes a forward truck 2|, and a rear truck 22, supported respectivelyon forward wheels 23, and rear wheels 24. The forward truck 2| is rigidly secured to two side plates 25, preferably having substantially the outline" indicated in Figures 1 and 2. In place of either such truck, I could support one end of the scraper on the propelling vehicle. a

These parts constitute parts of the frame of the implement, and are connected together in such a way as to enable the scraper blade 26, which is located forward of the bucket 21, to be raised or lowered at will with respectitothe ground level. In order to accomplish this, the rear truck 22 is preferably providedv with rigid forwardly projecting side arms 28 that extend forwardly to a point about midway between the two trucks, at which point the arms 28 are connected by pivot bolts or pins 29 to the side plates. L

Rigidly secured to the side plates 25; I provide a transverse lower beam 30, and an upper beam 3|, which latter beam may if desired be made of lighter construction than the lower beam. #The inclined scraper blade 26 is preferably rigidly secured to the side plates 25, and cuts into the earth when the bucket 21 is being filled. Adjacent the blade 26 and preferably at its rear edge, the bucket 21 is pivotally mounted on a transverse pivot bar 33.

When the bucket 21 is in the position of rest,

as indicated in Figure 1, the stop-bracket 84, carried by the rear face of the bucket, rests against a bumper or bumpers ii on the top of lower beam 30, and this limits the downward movement of the bucket.

All the foregoing is conventional, and for the purposes of my invention is merely illustrative, inasmuch as my apron could be used with scrapers of quite different type. t

We now come to the subject-matter of my invention, namely my apron. In place of the conventional apron, I employ the following. My apron bottom is in two sections, one of which 18 is carried rigidly by conventional apron-arms 31 pivoted to the side plates 25, as at 38, and the other of which 39 is carried rigidly by a pair of auxiliary arms 40, which arms are pivoted to the arm 31, as at 4|, and to a pair of links 42, as at 43. Links 42 are in turn pivoted to the side plates 25, as at 44. Other means than links 42 could perhaps be employed to constrain auxiliary arms 40.

For simplicity in nomenclature, the following terminology will be used in my claims. Apronarms 31 will be referred to as apron-arms." Apron-section 36, will be called the "main apronsection. Apron-section 19,-plus auxiliary arms 40, will collectively be referred to as the auxiliary apron-section."

If apron bottom section 39 had been rigid with arms 31, as in the conventional apron of the prior art, it would have extended up to corner 41 of arms 31 in Figure 2, and thus would have necessitated locating ropes 45 and 48 considerably higher. Or, alternatively, the apron could have been limited in its rise, by bottom section 39 striking rope 45.

But, in my invention, section 39 folds down out of the way as shown in Figure 2.

Furthermore this relative angular movement breaks away any sticky dirt packed in my apron.

By lip in my claims, I mean merely that edge of the apron which effects closure with the rest of the scraper.

As shown, rope 45 serves to dump. Rope 48 serves to raise and lower the apron, being bent around a cam-surface 49 on bottom section 39 when the apron is in lowered position. If desired, to give rigidity to this cam-surface 49 and bottom section 39, the cam-surface may extend clear across the bottom from one auxiliary arm 40 to the other. The depth-control rope 48 is also shown. But the particular means for performing the four functions listed at the beginning of this specification forms no part of my invention.

Having now described and illustrated oneform of my invention, I wish it to be understood that my invention is not to be limited to the specific form or arrangement of parts herein described and shown.

I claim:

1. In a carry-type earth-moving scraper, comprising digging means, main dirt-holding means, and dumping means, the combination, with said main dirt-holding means, of: a two-section dirtretaining apron, comprising a main apron-section and an auxiliary apron-section; means for raising the apron; apron-arms, rigid with the main apron-section, and pivoted on an axis fixed at all times with respect to the main dirt-holding means.said axis lying to the rear of and distant from the apron, said auxiliary apron-section being pivoted to the apron arm adjacent theforward edge of the main apron-section to form a continuation thereof in all positions of the apron; and means constraining the two sections of the apron, as the apron is raised, to constantly change their angular relation toeach other.

2. A dirt-holding instrumentality according to claim 1, further characterized by the fact that the constraining means is links, pivoted to the auxiliary apron-section at a point spaced from the pivot of the apron-arms to the auxiliary apronsection, and pivoted on an axis fixed at all times with respect to the main dirt-holding means, said axis lying to the rear of the pivotal connection between the links and the auxiliary apron-section.

and spaced from the first-mentioned axis.

3. A dirt-holding instrumentality according to claim 1, in which the constraining means is links, pivoted on an axis fixed at all times with respect to the main dirt-holding means, said axis being spaced from and forward of the first-mentioned axis, said links also being pivoted to the auxiliary apron-section at a point spaced from the pivot of the main apron-arms to the auxiliary apronsection.

4. A dirt-holding instrumentality according to claim 3 further characterized by the fact that the relative location of the pivot axes and pivotal connections, and the relative effective lengths of the arms and links, are such that, as the apron is raised, the auxiliary apron-section rotates faster and further than, although in the same sense as, the main apron-section, thereby reducing overhead clearance.

TREVOR O. DAVIDSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 140,175 Warren June 24, 1873 2,164,461 Le Bleu July 4, 1939 2,349,576 Daniels May 23, 1944 

